Mechanical ink pencil



Sept. 9, J. Q WAHL MECHANICAL INK PENCIL A zzgl-VENTOR.

' Joh/z C. WMM,

J. C. WAHL MECHANICAL INK PENCIL sept. 9, 1947.

5 Sheets-Sheet 2 'Filed Sept. 11, 1944 INVENTOR.

. BY Jozm C. Wad,

Sept. 9, 1947. J. c. WAHL' MECHANICAL INK'PENCIL Filed Sept. l1, 1944 5 Sheets-Sheet 34 NQNNQQ Patented Sept. 9, 194'? John C. Wahl, Chicago, Ill., assignor to Eversharp, Inc.,` Chicago,v,lll., a corporation Yof Delaware Application September 11, 1944, Serial No. 553,515

This invention has to dovwith mechanical ink pencils of the type in which the ink is transferred -to the sheet ofpaper or other material by asmall ball which is rotatably: mounted in the tip.f V

Y ne of theobjects of the invention is to provide a ball-,tipped-writing implement of new and improved construction for use with a replaceable ink-cartridge, which-.writing implement willoperate efficiently with ink of paste-like consistency fed tothe same from the cartridge and will apply the` inkA tothe paper in a smear-proof line of any desired iineness.

, Another objectis to provide a writing imple-v ment of the type described which is inexpensive to manufacture iand is composed of a minimum number of parts, which parts are of simple and -v -3 Claims. (01.12042) sturdy design and are easy to assemble and diss assemble.

Another object is to provide, for use in such a writing implement, a separate self-contained ink reservoir in the form'of areadily replaceable cartridge :capable of retaining and feeding suf-` cient-paste typeink to last for a long period ottime.,

L.Still another yobject-is to provide a paste type inkreservoirof novel construction which is very cheapztovv manufacture and upon beingr emptied can Abeeither refilled or discarded, as desired.

-siWhilethc foregoingzstatements are indicative in ageneral. way rof thenature of the invention, other -m'orespecificr objects and advantages will beiy apparent to those skilled in the art upon a full understanding of the construction. relative arrangement and operation 'of the several parts constituting the new writing implement.

AALY-few illustrativeembodiments of the inventi'onlarepresented herein,l but it will of course be understood that such embodiments have been chosen primarily for the purpose of exemplification:larjldk that the invention is susceptible of incoijporationA *in Astill other 'structurally' modied formsjcomlilg equally within the sco-pe of the appendedclalms.

" `Injthe accompanying drawings:

IFig. `1 isi aside View of a writing implement` constructed in accordance with Vthe invention,V

withfthe cap shown in longitudinal section;

VFigLZA is aV longitudinal section through the front'portion ofthe writing implement;

Ftgy-2Blis a Ysimilar, section through the rema `der of the writing implement; Y

f gdisuav side view of the replaceable ink 1dge;. n

2 Fig. 4 is a longitudinal section through thecartridge, taken on the liney 4-4 of Fig. 6; -r

Fig.Y 5 is a similar section, taken onthe line 5 of Fig. 6;` f

Fig. 6 is a front end view of the cartridge; Fig. 7 is a rear end view of the same; v Fig. 8 is a transverse section through the car tridge, taken on the line 8-8 of Fig. 3; f f,

Fig. -9 is another transverse section through th cartridge, taken just rearwardly of the front closure member, on the line 9-9 of Fig. 3;

Fig; 10 is a similar section, taken just forwardly of the rear closure member, on the line Ill-I0 ofFig. 3; Y f

Fig. 11is a fragmentary longitudinal section through the cartridge, taken on the line I I-II of Fig. 10;

Fig. 12 is a longitudinal section which is identical with Fig. 5, but shows the open ends of the ink passages sealed off before use by removablef stopper members; l

Fig. A,13 is a side view of a plunger suitable for use in initially advancing. the ink from the reservoir into the bore leading to the ball at thetip; and Y Fig; 14 is a partially sectioned side view modied form of reservoir.

, The writing implement shown in Figs. 1 to 12,

inclusive, will first be described. This imple.

ment includes primarily a head I0, a tip II which contains an ink transferring ball I 2, a barrel I3, and a reservoir I4.

The head Ill-Which is preferably made of light plasticv materialis provided with a longitudinally extending bore I5 through which the ink passes in advancing from ythe reservoir I4 into the tip II. The front portion of the bore I5 is enlarged in diameter and is interiorly threaded at I6 for the reception of an exteriorly threaded portion I'I of the tip II. The outer surface I8 of the head I0 is of conical form and tapers forwardly toward the tip I I to provide a conveniently shaped linger grip, while the outer surface I9 of the tip I I is also of conical form and tapers forwardly. Y -Y The tip I I which is preferably made of metal--` is'provided with a longitudinally extending bore 20 which registers with the bore I5 in the head z I Il, The bore 2l) opens forwardly into a bore 2I of reduced diameter, and the bore 2| in turn opens forwardly into a bore 22 of still further reduced diameter. The bore 22e-which is of very minute size-opens forwardly into the center of a small socket 23 in `which the ball I 2 isvmounted. TheA socket 2 3 opens forwardly and the ball is simplev piston-like retained in the same in a partially projecting position by a fine inturned annular edge 24. The ball I2 is rotatably mounted within the socket 23 between the edge 24 and an annular shoulder 25 present between the bottom of the socket and the front end of the bore 22. The inkwhich is preferably of viscose or paste-like consistency and designed particularlyfor feeding by-capillary .ac-y tionis fed to the rear surface of the ball I2 from the bore 22. Movement of the writing implement with the ball I2 in contact with the surface to be written upon causes the ball to rotate within the socket 23, transferring the ink from the ball onto such surface in a thin uniform hlm, much after the fashion of Aoffset printing. The head I in addition to mounting the tip I I pro- Vides a rigid support for both lthe barrel I3 and the reservoir I4.

The outer surface of .the rear portion of the head Ill is reduced in diameter and is eXteriorly threaded at '2.5. The iront end. .of the barrel .I3 is interiorly threaded -at 21 .for engagement with the `threads on the head, with the Aouter surface of the barrel disposed substantially ush with the vadjoining surface -of the head Ill. The front end of thebarrel 1'I3 is adapted `to havea cap 2S sleeved Aover the same, and lis eXteriorly ythreaded at 29 for engagement with threads '3G on the ins-ide Aof the cap. I-n the closed position of lthe cap an annular shoulder '35! on the inside of the same abutsy against an annular shoulder 32 on the outside 4of the tipA II w-hereb-yto provide an air-tight seal for the front end of the tip. The barrel I3 is preferably made of the same material as'the head I-Il and -is vclosed atits lrear end.

y'Zhei'esei'voi-r `i4 is of unique construction. lt is releasably secured to the rear end of the thead I'ILindepend-ently-of both the tip I-I and the barrel I3, in slightly spaced concentric relation to the barrel. The reservo-ris a separate self-contained cartridgeor filler capable of holding sufficient paste-type ink to last for say six months or a year. vSuch a cartridge can be either removed and refilled when empty or 4else discarded 'and replaced by a new full cartridge, all lwithout Idisturbing the mounting-of t'hetip Il with-in the head I0.

'Thereservoir Myconsists of ya 'small rod-like member 35 'of generally cylindrical shape which contains a number of longitudinally extending capillary-like passages '36, 31, 38 33 Yand 43. The

' member 35 is closed at its ends by caplifke cover members '4l and '42 Ahaving rims '43 which Aaredisposed flush with Aand permanently 7secured yto the'mcmber 35. The member 35 can be 'molded 0r extruded from hard rubber Ior other suitable material; and the covers 4I Yand 42 lcan be 4made ofthe same 4material and fastened by `cement or other means to Ather/ends ofthe member v.35.

The Apassage 36 is located wat the .center Lof the member while the lpassages 31, "3S, 39 and jllil are located in za, circle about the passageV 36, in spaced parallel relation to both that passage and each other. The 'front cover member '41 Acloses off the front ends of all of the passages withy the exception 'of the center passage 36, and is 1ero-y vided with'anexteriorly threaded nipple 44 which projects -forwardly and contains a bore 45Y which registers lwith 'the Vfront end of the passage 36. The rear cover member '42 closes olf the rear ends of all `of the passages with the exceptionbf one o'f the side passages-namely, the side 1passage 4'0-asmall hole 346 being provided in the-member 42inregister withthat passage. l y

The passages .35,.31,3'8,i39 and ill areeonnected 4 together in series and together form one long tortuous ink retaining and feeding conduit. The connections between the passages consist of two arcuate grooves 41 and 48 formed in the front face of the member 35 between the latter and the inside face of the front cover member 4I, and arcuate and radial grooves 49 and 50 formed in the rear face of the member 35 vbetween the latter and the inside face of the rear cover vmember 42. The rear end of the bore I5 in the head IIJ is threaded at 5I, and the nipple 44 is adapted to be screwed into the same into a position in which the front face 52 of the front cover mem. ber 4I firmly abuts against the rear face 53 of the head.

All of the passages 36, 31, 38, 39 and 40 in the reservoir are adapted to be initially lled with the ink. As the ink is used up at the ball I2 it Works itself forwardly with a capillary-like action in the passages until the latter have been more or less completely .emptied A"Starting at .the rea-rA open .end of the side passage 40, .the 'ink travels forwardly infthat pas-sage to the front end of the same, then laterally in the arcuate groove 41 into the front end of :the side passage 3:9, then rearwardly in that pas-sage to the rear end .of .the same, then laterally in the .arcuate groove '49 into the rear end of the-side passage VA38, then forwardly in that passage'to the f-ront end of the same, then laterally in the yarcuate .groove 48 into 'the front end of the vside vpassage v317, :then rearwardly in that passage to the rear end of the same, then laterally i-n tt'l'1e`radia1 groove .5@ .into the rear gend fof the center passage .3.5, `and .then vforwardly in that passage, :discharging at the front endof :the latter through .the Vnipple v44 :into 'the :bore 'I5 Ain =the head Ii0 Before the reservo-ir I4 is inserted in they/.rit-V ing `implement the open `ends of the passages l36 and .idd are :sealed lofi, :a cap .54 Vor other .closure being "applied tothe nipplef44 and 4aplug 55 Aor other `:closure bei-ng `applied to fthe atmospheric vent hole 4:3. As will be observed, the-1cap-154 closes off the bore 45 in the nipple at a point flush .with the forward extremity of v.the same, thus; allowing the fbore '45 t0 .be Completely ,Q g. cupied :by rt-he lwhen ftlrecap :is fin pla'cejanfd prior tov .insertion in thev writing implement. When the, reservoir is ready -to be inserted the cap 54 and plug 55 are removed and -d-iscarded.

To get the .in-k to move initially :into the bore E5 lthe head til a-,piston--like plunger 56 of anysuitable construction, furnished with the reservoir, :may be pushed into thev rear `end of the passage A4t farv enough to force "the :inl:

through fthe fbore -I 5 up to the ball ft2. The Areservoir I l contains all ofthe inkiused'in Athewriting .implement-the .barrel I3 merely serving as an .enclosure for .the reservoir.

:une passages .sa s1, es, sa and mare shown as circular. in cross .section .but `the same. might be .of .anyother shape. of the passages should be sufficiently small .to

give a satisfactory capillary feed, while at v,the

The cross sectional .area

enough to work forwardly in the passages of the reservoir while not so thin as to seep rearwardly from the open end of the last passage Ml.

In Fig. 14 a modified cartridge type reservoir is shown which consists of a ne copper tube 51 wound-into a compact helix. The front end 58 of the tube is straightened out for a short distance and is equipped with an exteriorly threaded sleeve 59 which is adapted to be screwed into the threaded rear end of the bore l5 in the head l0. Before use the front end 58 of the tube is closed by a screw cap 60. The rear end 6| of the tube is also straightened out for a distance suiiicient to permit the insertion and movement of the priming plunger. The rear end 6I, which is left open when the reservoir is in place in the writing implement, is initially closed by a screw plug 62, which plug is adapted to be removed at the same .time as the cap 60.

The pen of this invention is similar in some respects to a mechanical pencil, especially as to feel and character of the writing impression and feed and manner of replenishing the writing medium.

I claim:

1, An ink cartridge for insertion in a iilled condition in the barrel of a pen shaped writing implement of the rotatable ball type; said cartridge comprising a solid rod-like member of such diameter as to fit slidingly within the barrel, said member being provided with a plurality of longitudinally extending passages and a plurality of cross channels between the ends of certain of said passages, whereby to connect all of said passages in series to form one long ink holding vein in which a supply of viscous ink is adapted to be held, a closure member at the rear end of said member for forming the channels in that end into closed conduits, another closure member at the front end for the same purpose, said front closure member being provided with a forwardly extending nipple of reduced diameter containing an axially extending bore in communication with the front end of the ink feeding vein, which bore terminates at the front end of the nipple, means on the outside of the nipple intermediate the ends of the latter for securing the same in a forwardly adjusted position within the surrounding barrel of the writing implement, and means for venting the rear end of the ink holding vein to the atmosphere.

2. An ink cartridge for insertion in the barrel of a ball point pen, said ink cartridge being provided adjacent its front end with an exteriorly threaded portion for screw threaded engagement within the front end of the barrel of the pen, said cartridge containing a long small diameter bore which extends'longitudinally of the cartridge and is adapted to contain a quantity of viscous ink in uninterrupted continuous vein form commencing at the front end of the cartridge, .the cross-sectional area of the bore being such relative to the W characteristics of the ink as to prevent the ink from flowing under gravity alone in either direction irrespective of the position of the cartridge when the front end of the bore is closed or connected with the pen, the front end of the bore being flush with the front end of the cartridge and being adapted to be closed off flush before use by a screw cap, and the rear end of the bore being open.

3. A Writing implement of the rotatable ball type, comprising a pen-shaped casing and a replaceable ink cartridge within the casing; said casing being provided in its front end, with a forwardly opening socket, a writing ball rotatably mounted in the socket, and an axially extending ink bore in communication with the socket, and being provided at the rear end of the bore with a rearwardly opening interiorly threaded recess of larger size than the bore, and a chamber of still larger size into which the recess opens; and said cartridge being provided with an elongated body portion in which a supply of viscous ink is adapted to be held in uninterrupted continuous vein form, which body portion is housed within the chamber of the casing, and a forwardly projecting nipple of reduced size at the front end of the body portion, which nipple is exteriorly threaded for screw threaded engagement with the recess and contains an axially extending ink bore of substantially the same cross-sectional area as the bore in the front end of the casing for uninterrupted endwise communication with the bore.

JOHN C'. WAHL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,107,424 Platt Feb. 8, 1938 1,179,086 Foster Apr. 11, 1916 1,500,426 Townsend July 8, 1924 1,327,729 Paschall Jan. 13, 1920 233,924 Downes Nov. 2, 1880 1,493,680 Koepsell May 13, 1924 1,917,846 Klopsteg July 18, 1933 1,426,200 Kovacs Aug. 15, 1.922 1,980,625 La Forest Nov. 13, 1934 1,211,457 Gaines July 2, 1918 1,831,751 Rado Nov. 10, 1931 1,712,141 Folk May 7, 1929 1,811,763 Schweiger June 23, 1931 2,381,898 Gergeley Aug. 14, 1945 841,222 Bowman Jan. 15, 1907 751,256 Cameld Feb. 2', 1904 2,397,229 Biro- Mar. 26, 1946 OTHER REFERENCES Knotts Catalog, 1916, pages 133 and 305. 

